Humidifier



FIG. 1 is a top perspective view of humidifier showing our new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a side elevation view thereof, the opposite side being a mirror image thereof.

The rear and bottom view of the embodiment form no part of the claimed design. The broken line showing of environmental structure in FIGS. 1-4 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a humidifier, as shown and described. 